COMMISSION 27 OF THE I. A. U.
          INFORMATION BULLETIN ON VARIABLE STARS
                       NUMBER 830

	                              Konkoly Observatory
        	                      Budapest
                	              1973 October 2



            SECONDARY MINIMUM FOR WY HYDRAE


WY Hydrae was observed photoelectrically on the UBV system on one
night in January 1970 at the No. 1 36-inch telescope of the Kitt
Peak National Observatory. The observational data are of sufficient
accuracy only for a minimum determination since the data were 
obtained through intermittent clouds. The observations are given in
Table I. Columns 1, 2, 3, and 4 in Table I list the heliocentric
Julian date, and the differential V, (B-V), and (U-B) magnitude and
color indices, respectively. The differential measurements are in
the sense variable minus comparison. Star "c" (Solovyev, Per.Zv. 12,
262, 1958) was used as primary comparison star. There are just 
enough observations to obtain an approximate time of secondary minimum, 
namely JDhel 2440612.8627 +/- 0.0015d (estimated). Comparison of 
this observed time of minimum with that predicted by the light elements
given by Koch, Sobieski and Wood (Publ.Univ.Pennsylvania,Astr.Ser.
Vol. 9., 1963) gives an O-C of -0.029d for this secondary minimum.

                   	Table I
JD hel.    				JD hel.
2440612	DeltaV  Delta(B-V) Delta(U-B)	2440612	DeltaV Delta(B-V) Delta(U-B)
	  			
.8525	-0.128m  -0.180m   -0.112m 	.8952   -0.469   -0.198    -0.128
.8543   -0.100   -0.184    -0.127 	.9042   -0.589   -0.204    -0.148
.8627	+0.264   -0.306    -0.274 	.9063   -0.523      -          -
.8652	+0.300   -0.408    -0.304 	.9102   -0.617   -0.192    -0.166
.8704	-0.090   -0.168    -0.140 	.9123   -0.620   -0.150    -0.168
.8723	-0.118   -0.176    -0.117 	.9210   -0.734   -0.194    -0.114
.8769	-0.212   -0.173    -0.142 	.9232   -0.730   -0.174    -0.120
.8790   -0.250   -0.153    -0.166 	.9288   -0.726   -0.182    -0.117
.8840	-0.311   -0.199    -0.150 	.9307   -0.734   -0.192    -0.134
.8861   -0.349   -0.180    -0.153    	.9345   -0.778   -0.205    -0.140
.8931   -0.453   -0.200    -0.128    	.9367   -0.771   -0.224    -0.119

This work was supported by a travel grant from the Louisiana State
University Council on Research.



                           ARLO U. LANDOLT
                       Louisiana State University
                       Baton Rouge, Louisiana 70803




     NEW ELEMENTS OF THE ECLIPSING BINARY RT ANDROMEDAE


It is well-known that the eclipsing binary system RT And presents
some problems on the variability of the light curve between the minima 
as well as on the asymmetry of both minima.
Since the observational material is very poor and the elements of
the system are uncertain, 1268 observations were obtained during the
period October 1 - 8, 1971 with the aim to get the photometric elements. 
The observations were performed at the Ondrejov Observatory,
using the 65 cm Cassegrain telescope. The observed curve (normal points)
is plotted in the Figure.

                           [FIGURE 1]

We found the following constants of rectification and photometric elements 
for the system: A_0=+0,9702 +/- 0,0015; A_1=-0,0066 +/- 0,0019,
A_2 =-0,0268 +/- 0.0022; B = +0,0075 +/- 0,0010; B_2=+0,0002 +/- 0,0012.
k= 0,696; r_s = 0,247;  i = 87d; L_g = 0,8530; L_s = 0,1470; J_g/J_s = 2,90;
x_g = x_s = 0,80.





                                 AL. DUMITRESCU
                               Astrophysical Section
                              of Bucharest Observatory